Crop and Lock, available for both Windows 11 and Windows 10 v2004 (19041) or newer, has two modes — a non-interactive Thumbnail crop that’s essentially a live feed of the area you select that updates with the page, and a “Reparent” mode that Microsoft writes is more interactive, but could have compatibility issues with some apps.
You’ll need to make sure the window you want to crop is selected before you enter the shortcut — you can’t just grab any old app window on your screen.
Our own Sean Hollister gave the feature a spin, making a thumbnail crop of his Steam downloads and another crop of his office lights from Home Assistant, so he could keep a small window of only those controls. He found that creating a micro web browser with the Reparent mode was nice, but only allowed for vertical scrolling.
Sean noted that when you close out of the cropped app window, the former, full window reappears.
Microsoft lists a few known issues:
Cropping maximized or full-screen windows in “Reparent” mode might not work. It’s recommended to resize the window to fill the screen corners instead.
Some UWP apps won’t react well to being cropped in “Reparent” mode. The Windows Calculator is a notable example of this.
Applications that use sub-windows or tabs can also react poorly to being cropped in “Reparent” mode. Notepad and OneNote are notable examples of applications that react poorly.
Crop and Lock was added to PowerToys version 0.73.0, which GitHub shows was released two days ago for both X64 and Arm64 architectures.